If you have a slip on vs OEM and have put K&N type pods on it without doing anything to tune it, such as still running the OEM tune I don't even have to guess, you are running lean. Go to the resources tab in the banner at the top of the page and search through it to find something that would be close to what you want. All things considered you may be able to get away with using the Nels Tune but you really should get it on a dyno and done properly.
bob